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Biomedical subjects

X R Wang

Publications and source records attributed to X R Wang.

At least 55 records · Page 3Linked to original sources
PubMed1999

Selection effects on an estimation of long-term changes in pulmonary function.

To reveal the association of initial pulmonary function level with subsequent mortality and participation in a follow-up reexamination, a prospective cohort study was performed. Female residents in a volcanic area of southern Kyushu, Japan, were followed up for their vital status and the pulmonary function 15 years after they received the first pulmonary function test. A cohort of 512 Japanese female residents who were examined for pulmonary function as indicated by forced expiratory volume and forced expiratory volume in one second was measured in a baseline examination in 1980. After 15 years, 35 females were lost to follow-up. Of the remaining 477 females, 340 and 137 females provided good and poor levels of pulmonary function tests (PFT) at baseline, respectively. Mortality by 1995 in the poor PFT group was significantly higher than that in the good PFT group (33.6% vs 9.4%). The mortality differences were still highly significant when the 35 lost cases were included as all alive. Among the 399 survivors, the nonparticipation rate in the reexamination in 1995 was significantly higher in the poor PFT group than that in the good PFT group (80.2% vs 69.5%). The results of the present study, a longitudinal study of pulmonary function, provide evidence of selection effects due to death or failure to participate in a subsequent reexamination.

Adult↗
PubMed1999

Phylogenetic relationships of Eurasian pines (Pinus, Pinaceae) based on chloroplast rbcL, MATK, RPL20-RPS18 spacer, and TRNV intron sequences.

The sequence divergence of chloroplast rbcL, matK, trnV intron, and rpl20-rps18 spacer regions was analyzed among 32 Pinus species and representatives of six other genera in Pinaceae. The total aligned sequence length is 3570 bp. Of the four sequences examined, matK evolved much faster than rbcL in Pinus and in other Pinaceae genera. The two noncoding regions did not show more divergence than the two coding regions, especially within each Pinus subgenus. Phylogenetic analyses based on these four sequences gave consistent results and strongly supported the monophyly hypothesis for the genus Pinus and its two recognized subgenera. Pinus krempfii, the two-flat-needle pine endemic to Vietnam, was placed in subgen. Strobus and showed closer affinity to subsect. Gerardianae. The ancient character of sect. Parrya is further confirmed. However, monophyly of the sect. Parrya is not supported by our data. Among the Eurasian pines of subgen. Pinus, Mediterranean pines formed one clade and the Asian members of subsect. Sylvestres formed another. The Himalayan P. roxburghii showed considerable divergence from all the other hard pines from both regions. Pinus merkusii was distinctly separated from all the Asian members of subsect. Sylvestres. The implications of our results for Pinus classification are discussed.

Journal Article↗
PubMed1999

Urinary follicle stimulating hormone can be used as a biomarker to assess male reproductive function.

AIM: To develop an algorithm for use in population-based studies to assess testicular function by measurements of total urinary follicle stimulating hormone (FSH). METHODS: Total concentrations of urinary FSH were measured in a group of 44 men at the University of California, Davis (UCD) and were compared to FSH measurements in serum. On the basis of these and other published data, a urinary FSH value of >2 ng/mg creatinine (Cr) was selected as the cutoff point to identify men with elevated serum FSH ( > 12 IU/L) or low sperm counts ( < 20 million/mL). RESULTS: The sensitivity and specificity of this algorithm for detecting elevated serum FSH in a group of 58 agricultural workers in the People' s Republic of China were 100% and 50%, respectively. The sensitivity and specificity of this algorithm for detecting low sperm counts in a population of 105 infertility patients at UCD were 58 % and 76 %, respectively. CONCLUSION: This test may have particular value in identifying populations with no evidence of testicular toxicity, and in which labor-intensive semen studies may not be feasible.

Biomarkers↗
PubMed1998

RNA editing in gymnosperms and its impact on the evolution of the mitochondrial coxI gene.

Sequence analysis of the mitochondrial coxI gene in eight gymnosperm species revealed a high rate of nonsynonymous nucleotide substitutions with a strong (98%) predominance of C-T substitutions. Further analysis of the corresponding coxI cDNA sequences showed that all the non-synonymous C-T changes in the coxI genomic DNA sequences were eliminated by RNA editing resulting in nearly identical mRNA (amino acid) sequences among the species. Pronounced variation in the number and location of edited sites was found among species. Most species had a relatively large number of edited sites (from 25 to 34). However, no RNA editing of the coxI sequence was found in Gingko biloba or Larix sibirica. The sequence composition of the investigated coxI fragment suggests that the coxI gene in G. biloba and L. sibirica originated from edited mitochondrial coxI transcripts by reverse transcription followed by insertion into the nuclear genome or back into the mitochondrial genome. Our results also demonstrate that where there are a large number of edited sites, RNA editing can accelerate the divergence of nucleotide sequences among species.

Amino Acid Sequence↗
PubMed1998

A silicosis patient presenting with an enlarged supraclavicular lymph node.

A stone splitter was discovered to have an enlarged supraclavicular lymph node which showed nodules with bi-refringent crystals on histological examination. He had worked in a dusty environment for more than 10 years with ineffective respiratory protection. He gave a history of occasional cough with blood-stained sputum for 10 years for which no definite diagnosis was made. Silicosis (classified as type s/s with profusion 1/1) was confirmed after his chest radiographs were reviewed. The presentation was unusual and illustrated the importance of an occupational history in clinical practice.

Clavicle↗
PubMed1995

Expression of kappa opioid receptors in human and monkey lymphocytes.

mRNA encoding the kappa opioid receptor gene sequence was identified and isolated from various human lymphocytic cells: CEM x174 (a hybrid of T and B origin) cells, Jurkat-T4 cells, human peripheral blood mononuclear cells (PBMC) and purified CD4+ cells. Analyzing the cDNA sequences of RNA transcripts spanning the putative second extracellular loop, which has reported dynorphin specificity, and the seventh transmembrane domain revealed a 100% and 95% homology in amino acid sequence to corresponding kappa opioid receptor sequences in human placenta and rat brain, respectively. Expression of a similar kappa opioid receptor sequence could be detected in normal monkey PBMC but not in monkey PBMC in which the CD4+/CD8+ cell ratio (or CD4+ cell number) was significantly reduced due to prolonged SIV infection. These findings suggest that human and monkey lymphocytes constitutively express kappa opioid receptor mRNA.

Amino Acid Sequence↗
PubMed1994

Bioaccumulation of the rare earth elements lanthanum, gadolinium and yttrium in carp (Cyprinus carpio).

Widespread use of the rare earth elements (REEs) in China for agricultural purposes, together with many other applications, has resulted in a remarkable increase of REE concentrations in the environment. The comparative bioaccumulations of representative light, medium and heavy REEs in a variety of tissues of carp (Cyprinus carpio L.) were investigated for an evaluation of their impacts on aquatic animals. The fish were exposed continuously to solutions containing 0.50 mg litre(-1) of each element for 45 days at pH 6.0 and sacrificed at time intervals. Skeleton, muscle, gills and internal organs were analysed for REE contents. A method using cation-exchange resin separation and ICP-AES determination was developed for the quatification of individual REEs. The results show that carp has low ability to take up the REEs under the experimental conditions. The order of REEs under the experimental conditions. The order of maximum bioconcentration factors was mostly internal organs > gills > skeleton > muscle. Neither synergistic nor antagonistic effects of the mixed REE solutions for carp were observed. The relative distributions of different REEs in the investigated tissues exhibited similar patterns. Among the selected tissues studied, the concentration of a heavy REE (Y) was the smallest, while concentrations of a medium (Gd) and a light REE (La) showed only a slight difference.

Journal Article↗
PubMed1994

[Traditional Chinese medicine and Western medicine treatment for severe intractable head injury].

38 cases of severe intractable head injuries were treated by TCM-WM treatment, the survival rate was 68.4%, which was difficult or ineffective for Western medicine treatment. The author lay emphasis on taking the following measures: (1) Place nasal feeding tube in the nose as early as possible; (2) Take Zenye Tang and Shengmai Yin as chief prescription for nourishing Yin and replenishing Qi; (3) Take large dose of citicoline, Angong Niuhuang Wan and Xuefu Zhuyu Tang to promote resuscitation; (4) When pulmonary infection was serious and antibiotic ineffective, Shashen Maidong Tang and Ditan Tang etc. could be used.

Adolescent↗
PubMed1993

A comparison of medium-chain and long-chain triglycerides in surgical patients.

Available lipid emulsions made from soybean or safflower oil are classified as long-chain triglycerides (LCT). In contrast, medium-chain triglyceride (MCT) emulsions have different physical properties and are metabolized by other biochemical pathways. To compare the differences between these two fat emulsions, the authors studied 12 surgical patients and 6 volunteers. These subjects were randomly assigned to receive parenteral nutrition with MCT or LCT emulsion. Measurement of arterial and venous concentration differences across the forearm demonstrated that muscle utilization was significantly improved with MCT administration. There was also a trend toward improved nitrogen balance in the MCT group, and less weight loss in the postoperative period also was observed in this group. During the fat clearance test, the serum ketone concentrations were significantly higher in the MCT than the LCT group. The improvement in nitrogen retention may be associated with increasing ketone and insulin levels. Fat emulsions containing 50% MCT are safe for use in parenteral nutrition and may provide an alternate fuel that improves protein metabolism.

Drug Combinations↗
PubMed1993

[Effects of scoparone on hemodynamics in anesthetized rabbits].

The effects of scoparone (Sco), tetramethylpyrazine (TMP), and papaverine (Pap) on hemodynamics were compared in anesthetized rabbits. Three dosage levels (1.25, 2.5, 5 mg.kg-1, iv) were used for each agent. Sco lowered the blood pressure (BP), increased the cerebral blood flow (CBF) dose-dependently, but did not show significant influence on the femoral artery blood flow (FBF), the maximal decrease of BP, and the maximal increases of CBF being 15% and 20% of the control, respectively. In contrast, TMP raised the BP as well as increased the CBF and FBF simultaneously. Pap, however, lowered the BP, slightly increased the CBF and decreased the FBF only at large doses. The results suggested that Sco may cause a selective dilatation of cerebral blood vessels.

Animals↗
PubMed1993

[Effects of 6,7-dimethoxycoumarin on left ventricular function and hemodynamics in anesthetized cats].

Scoparone (6,7-dimethoxycoumarin 1.25, 2.5, 5 mg.kg-1) influenced the cardiohemodynamic functions in anesthetized cats. After i.v. injection the LVP-dP/dt loops and blood pressure were decreased. Both the contractile and relaxant functions of the left ventricle were inhibited. These were demonstrated by the reduction of dP/dtmax, Vmax, Vce-dp40, LVSP, prolongation of LVET, diminution of -dP/dtmax, and extension of the constant time of isometric diastolic pressure decay (T value). The preload of the left ventricle, LVEDF, was raised and the afterload (MAP, TPB) was decreased: The systolic volume, systolic index, cardiac output, and cardiac index were decreased slightly. The parameters TTI and TTI x HR, which reflect the myocardial oxygen consumption, were reduced. Furthermore, the heart rate was decreased at 5 mg.kg-1. The results indicate that scoparone could suppress the myocardial activity.

Animals↗
PubMed1991

Effects of intratracheal instillation of fenvalerate on the ultrastructures of pulmonary alveolar macrophages in rat.

On 1 d after instillation of fenvalerate (Fen) 0.19, 0.93, 4.66, and 23.3 mg.kg-1, and on 30 min, 4 h, 1 d, 4 d, and 7 d after instillation of Fen 4.66 mg.kg-1 by a single intratracheal instillation, respectively, the ultrastructural changes in rat pulmonary alveolar macrophages (PAM) were observed, and the toxicity indices (TI) were calculated. It was found that the ineffective dose of Fen was 0.19 mg.kg-1, and the threshold dose was less than or equal to 0.93 mg.kg-1 as well as the serious intoxication dose greater than or equal to 4.66 mg.kg-1. The results suggest that Fen is quickly toxic to rat lungs and quickly biodegraded in the lungs.

Animals↗
PubMed1990

[Purge of malignant cells from bone marrow by hematoporphyrin derivatives and light exposure in vitro].

During autologous bone marrow graft in treatment of malignant diseases, it is critical to purge malignant cells from the marrow. In the present study, the sensitivity to photodynamic inactivation of 3 leukemic cell lines was compared with their counterpart normal hematopoietic cells. After mouse leukemic L1210 cells were treated with a preparation of hematoporphyrin derivatives, YHpD, 10 micrograms/ml for 1 h and irradiated with black light (peak wavelength 395 nm, light intensity 0.6 mW/cm2) for 5 min, the survival rate of clonogenic cells decreased to less than 10%, while that of bone marrow granulocyte-macrophage progenitor cells (CFU-GM) in DBA/2 mice remained at nearly normal level (greater than 80%). Similar results were obtained when human leukemic HL-60 cells were compared to human CFU-GM and mouse leukemic L615 cells to CFU-GM in 615 strain mice. It is suggested that hematoporphyrin photoradiation may be useful for selectivity killing leukemic cells in bone marrow.

Animals↗